Electric control system for power boats



Sept. 12, 1933. E. GRAY ELECTRIC CONTROL SYSTEM FOR POWER BOATS ATTORN Y8 Patented Sept. 12, 1933 PATENT OFFICE un-"M ELECTRIC CONTROL SYSTEM FOR rowan OATS Edward Gray, Detroit, Mich., assignor to Edward Gray, Engineer, Inc., ration of Michigan Detroit, Mich., a corpo- Application February 24, 1931. Serial No. 517,878

1 Claim.

The present invention pertains to a novel electrical control system for power boats, particularly those driven by an internal combustion engine.

The principal object of the invention is to provide such a system wherein the engine may be initially turned over by a motor-generator which later operates as a generator when the propeller shaft attains a predetermined speed. Another object is to assure the direction in which the engine starts, inasmuch as it is known that two-cycle engines often start oppositely to the intended direction, thus causing collisions especially in close quarters. Moreover, the system according to this invention enables the vessel to be propelled by the motor-generator alone, for example when it is desired to run at lower speeds than permitted by the engine or when the engine is disabled. In the use of the motor-generator alone as the source of power, the battery for running the same may be charged by means of an auxiliary engine driving another generator. The latter system also is used for charging the battery when current is being consumed while the motorgenerator is not in'operation, as in lighting, heating or cooking aboard the craft while at anchor.

The invention is fully disclosed by way of example in the following description and in the accompanying drawing, in which- Figure 1 is a plan view of a power boat equipped with a control system according to the invention; and

Fig. 2 is a wiring diagram.

Reference to these views will now be made by use of like characters which are employed to designate corresponding parts throughout. In Figure 1 is shown a power boat indicated generally by the numeral 1 and adapted to be driven normally by an internal combustion engine 2 such as a Diesel engine. A propeller shaft 3 extends from the engine in the usual manner and carries a propeller 4 at the stern end. A reversible motor-generator 5 is also operable on the shaft 3, and a clutch 6 is inserted in the shaft between the engine and the motor-generator. A suitable linkage 7 for operating the clutch extends therefrom to the pilot house 8.

A battery of cells 9 is provided for driving the motor-generator to start the engine. A control for this apparatus is mounted in the pilot house and includes a series of fixed contacts 10 connected to various points of a starting resistance 11. The rotary element of the control includes two stepped contacts 12 and 13 at opposite sides of the fixed contacts 10. The control is actuated by means of a pivoted handle 14. When the handle is turned, the movable contacts turn in the opposite direction because of the pivotal mounting of the handle, as indicated in Figure 2. The contacts 12 and 13 are symmetrical with respect to the line drawn therebetween, and both operate in like manner in cutting out the starting resistance 11 progressively, regardless of the direction in which the handle 14 is turned. One of the end contacts 10 is joined by a conductor 15 to the positive terminal of the battery 9.

In the controller are also embodied four additienal fixed contacts 16, 17, 18 and 19. The contact 16 is connected by a line 20 to the remaining end conductor 10. The intermediate conductors 17 and 13 are connected respectively to the ends of a field 21 for the motor-generator 5. One of the terminals of the generatoris connected by a line 22to the negative terminal of the battery 9, and the other side of the generator is joined by a conductor 23 to the fixed contact 19.

The rotary element of the controller carries a pair of contacts 24 and 25 in line with the member 12. The contact 24 is adapted to bridge the fixed contacts 16 and 17, and the contact 25 to bridge the fixed contacts 18 and 19 when the handle 14 is pulled forward to drive the engine forward. In fact, the contacts 24 and 25 are in this position when the controller is in neutral, but at this time the circuit is broken at the starting resistance 11; but the length of the contacts 24 and 25 is such that they remain in engagement with the fixed contacts while the controller is being brought to full forward driving position. With the contact 12 bridging any or all of the fixed contacts 10, a circuit is formed from the positive side of the battery 9, through conductor 15, contacts 10 and 12, conductor 20, contacts 16, 24 and 1'7 to the field 21, thence through contacts 18, 25 and 19 to one of the terminals of the motor-generator 5, and from the remaining terminal thereof to the negative side of the battery 9.

The part of the controller for effecting a reverse drive includes a contact 26 of reversed C- shape adapted to engage the contacts 16 and 18, and another contact 2'7 of I-shape adapted to engage the contacts 17 and 19.

When the handle 14 is turned to put the engine 2 in reverse, the aforementioned position of the contacts 26 and 27 is eifected, while the contacts 24 and 25 are freed from the fixed contacts 16, 17, 18 and 19. A circuit through the battery 9 and motor 5, similar to that already described, may now be traced. This circuit will however include the contacts 26 and 27, the effect of which is to reverse the flow of current through the field 21, whereupon the engine 2 is reversed. In starting in either forward or reverse, the motor 5 cranks the engine and continues to operate .on the shaft 3 :until .the latter attains a certain predetermined :speed. 'When this speed is reached, the motor-generator commences to function as a generator to charge the'battery 9, through the action of an automatic switchrfievice 28 connected across the conductor 15 and field 21 and thereby adapted 'to short circuitat least a part of the controller. This device is of standard construction and as dikewise :adapted to operate the member 5-.-as ta motor when dhe shaft 3 falls below a predetermined minimum speed, whereupon it is maintained .in rotation, and the engine 2 is prevented from stalling.

An auxiliary engine 29 is also proviriedrnn the boat and is connected to a generator 30 which in'tumis adapted tooharge the' battery e-through conductors 31 anil'32. 'Thecharging however is controlled by -'a =switch 33 inserted in "one of the conductors and positioned inthe pilot houseA.

The-engine '29 may be'crankedby'hand, "or the member may *be -a motor-generator adapt- "ed first to crank the engine and then transform itself automatically into a generator driven by *the engine.

The various uses 'of this system will now be described. in starting the engine -2 through the motor-generator 5, the direction of rotation is definitely and positively determined by the -operation -of the handle 14 at the *controller. This is -a distinct advantage in 'connection with a two-cycle -engine, wherein the direction'of rotation is diten *opposite *to that intended. In manoeuvring in close quarters, rotation in the wrong direction dueto'ade'fectsuchas'a sticking 'valve,'d1ten Tesultsin'a collision.

It may also be desired to run the craft at lower speed than permissible by the engine 2, especially if the latter is a Diesel engine. In such case, the desired low speed is available through the motor-generator 5, and the clutch B-maybe opened through thelinkage 7 to avoid starting the-engine 2.

The auxiliary engine 29 and generator 30 charge the battery 9 when current is being con- :smned while the engine 2 is idle, as for lighting, heating or cooking aboard the vessel at anchor. inlsmifthe'engine 2 should become disabled, the vessel may be run into port by the motor-gen- .eratm' 5, 'in which case the battery 9 may be continuouslyrcharged from the generator 30.

gilthough a specific embodiment of the invention has 'been illustrated and described, it will be understood that various alterations in the details of construction may be made without departing from the scope of the invention, as indicated by "the appendedclaim.

"What I 'claim'is:

An electrical control system for power boats comprising an engine, a propeller shaft extend- 10o .ingtherefrom, a reversible motor-generator connected .to .said shaft, a battery for driving said motor-generator and starting said engine, said battery being adapted to be charged by said tmotorfgenerator, a reversing switch for said mom toragenerator, automatic meansIor causing said .mntor-generator .to operate as a generator to charge said battery on attainment of a given speed, .an auxiliary engine normally independent of said shaft, and .a generator coupled thereto i and connected .to said battery for charging the .same.

EDWARD GRAY. 

